Submission #1002689

#	Time	Username	Problem	Language	Result	Execution time	Memory
1002689		aykhn	Liteh and Newfiteh (INOI20_litehfiteh)	C++17	100 / 100	97 ms	124600 KiB

Main

#include <bits/stdc++.h>
 
using namespace std;
 
#define inf 0x3F3F3F3F

const int MXN = 1e6 + 5;
const int LOG = 20;

int dp[LOG][MXN][LOG];
int dp1[MXN];

signed main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  int a[n + 1];
  for (int i = 1; i <= n; i++) cin >> a[i];
  for (int i = 0; i < LOG; i++)
  {
    for (int j = 1; j + (1LL << i) - 1 <= n; j++)
    {
      for (int k = 0; k < LOG; k++)
      {
        if (!i)
        {
          dp[i][j][k] = (k == a[j] ? 0 : (k == a[j] - 1 ? 1 : inf));
        }
        else
        {
          dp[i][j][k] = min(dp[i - 1][j][k] + dp[i - 1][j + (1LL << (i - 1))][k], dp[i - 1][j][k + 1] + dp[i - 1][j + (1LL << (i - 1))][k + 1] + 1);
          dp[i][j][k] = min(dp[i][j][k], inf);
        }
      }
    }
  }
  for (int i = 1; i <= n; i++)
  {
    if (a[i] >= LOG)
    {
      cout << -1 << '\n';
      return 0;
    }
    dp1[i] = inf;
    for (int j = 0; j < LOG && i - (1LL << j) >= 0; j++) 
    {
      dp1[i] = min(dp1[i], dp1[i - (1LL << j)] + dp[j][i - (1LL << j) + 1][0]);
    }
  }
  cout << (dp1[n] >= inf ? -1 : dp1[n]) << '\n';
}
 

// 10
// 1 1 1 1 2 2 2 3 2 1

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70